TY - JOUR
T1 - High-power microwave surface flashover of a gas-dielectric interface at 90-760 torr
AU - Edmiston, Gregory
AU - Krile, John
AU - Neuber, Andreas
AU - Dickens, James
AU - Krompholz, Hermann
N1 - Funding Information:
Manuscript received September 30, 2005; revised December 2, 2005. This work was supported by the Cathode and HPM Breakdown MURI program funded and managed by the Air Force Office of Scientific Research (AFOSR). G. Edmiston and J. Krile are with the Center for Pulsed Power and Power Electronics, Department of Electrical Engineering, Texas Tech University, Lubbock, TX 79409 USA (e-mail: greg.edmiston@ieee.org). A. Neuber, J. Dickens, and H. Krompholz are with the Department of Electrical Engineering, Texas Tech University, Lubbock, TX 79409 USA (e-mail: A.Neuber@coe.ttu.edu, JDickens@coe.ttu.edu, HermannK@coe.ttu.edu). Color versions of Figs. 11–13 are available at http://ieeexplore.ieee.org. Digital Object Identifier 10.1109/TPS.2006.883392 Fig. 1. Overall system diagram for HPM surface-flashover testing. Setup includes multiaxis viewing of flashover events, allowing for a variety of high-speed diagnostics, including imaging, spectroscopy, and luminosity, in addition to power measurement diagnostics via a pair of directional couplers upstream and downstream of the sample.
PY - 2006/10
Y1 - 2006/10
N2 - The major limiting factor in the transmission of high-power microwave (HPM) has been the interface between dielectric-vacuum or, even more severely, between dielectric-air, if HPM is to be radiated into the atmosphere. Extensive studies have identified the physical mechanisms associated with vacuum-dielectric flashover, as opposed to the mechanisms associated with air-dielectric flashover, which are not as well known. Surface-flashover tests involving high field enhancement due to the presence of a triple point have shown that volume breakdown threshold (dielectric removed) is approximately 50% higher than the flashover threshold with a dielectric interface over the 90-760 torr range. In order to quantify the role of field enhancement in the flashover process independent of electron injection from metallic surfaces, the effects of the triple point are minimized by carefully choosing the geometry, and in some cases, the triple point is "removed" from the flashover location. Experimental results were presented, including the impact of gas pressure and the presence of UV illumination, along with temperature analysis of the developing discharge plasma and temporally resolved images of the flashover formation. These results are compared with literature data for volume breakdown in air, with discussion on the similarities and differences between the data.
AB - The major limiting factor in the transmission of high-power microwave (HPM) has been the interface between dielectric-vacuum or, even more severely, between dielectric-air, if HPM is to be radiated into the atmosphere. Extensive studies have identified the physical mechanisms associated with vacuum-dielectric flashover, as opposed to the mechanisms associated with air-dielectric flashover, which are not as well known. Surface-flashover tests involving high field enhancement due to the presence of a triple point have shown that volume breakdown threshold (dielectric removed) is approximately 50% higher than the flashover threshold with a dielectric interface over the 90-760 torr range. In order to quantify the role of field enhancement in the flashover process independent of electron injection from metallic surfaces, the effects of the triple point are minimized by carefully choosing the geometry, and in some cases, the triple point is "removed" from the flashover location. Experimental results were presented, including the impact of gas pressure and the presence of UV illumination, along with temperature analysis of the developing discharge plasma and temporally resolved images of the flashover formation. These results are compared with literature data for volume breakdown in air, with discussion on the similarities and differences between the data.
KW - Atmospheric
KW - Breakdown
KW - Dielectric surface
KW - High-power microwave (HPM)
KW - Surface flashover
UR - http://www.scopus.com/inward/record.url?scp=33750383668&partnerID=8YFLogxK
U2 - 10.1109/TPS.2006.883392
DO - 10.1109/TPS.2006.883392
M3 - Article
AN - SCOPUS:33750383668
SN - 0093-3813
VL - 34
SP - 1782
EP - 1788
JO - IEEE Transactions on Plasma Science
JF - IEEE Transactions on Plasma Science
IS - 5 I
ER -